Abstract: A printer comprises a printing section, a communication module for near-field radio communication with a portable terminal, a reception module, a first output module and a second output module. The reception module receives transaction information from an information processing apparatus. The first output module generates electronic transaction information according to the transaction information and outputs the generated electronic transaction information to the portable terminal via the communication module if the communication module establishes the near-field radio communication with the portable terminal. The second output module generates printing data of the transaction information and prints the generated printing data by the printing section if no near-field radio communication is established by the communication module.

Abstract: A serial printer apparatus comprises a print heat for printing on a medium according to a received character signal, a carrier on which the print head is provided and which runs the print head over an unprintable region and a printable region, and a control circuit for monitoring the running speed of the carrier and controlling the speed of the carrier by accelerating or decelerating the carrier while suppressing the amount of fluctuation of the speed at least in the printable region.

Abstract: The thermal head supporting device of the invention comprises a pair of positioning members disposed at both sides of a platen, a head press/release mechanism movable toward and away from the platen, and a head unit coupled with the head press/release mechanism. The positioning members are disposed coaxially with the platen. The head unit is formed of a head supporting member removably coupled to the head press/release mechanism with a predetermined play, a thermal head supported on the head supporting member and having a plurality of heating elements arranged in a straight line thereon and in confronting relationship with the platen, and a pair of engagement members attached to both sides of the thermal head adjustably for position, and each of the engagement members has a cutting formed therein allowing each positioning member to be removably fitted therein.

Abstract: Disclosed is a method for driving a printer carrier. One power source is connected via a constant current circuit to the carrier motor. Data storing means stores the current command data corresponding to the acceleration, constant speed printing and deceleration of the carrier motor. According to the method, the current command data from the data storing means is latched in synchronism with a clock signal. The latched data is converted to a current reference voltage. The output current of the constant current drive circuit is varied in accordance with the current reference voltage. Changing the current command data as desired makes it possible to adjust freely the torque of the carrier motor for acceleration and deceleration on a constant voltage from one power source.